Naproxene syntheses: electrophilic aromatic substitution on

Off-topic conversations and chit-chat.

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I came across a couple of electrophilic substitutions whose mechanism I can't understand.

The first one is a Friedel-Crafts acylation: the products are the ones indicated in the picture and they are separated before proceeding. No other byproducts are shown.
Image

Why did the acetyl go in pos. 6? As far as I know, When an electrophilic substitution is made on an activated substituted naphthalene, the electrophile will go in the substituted ring, in the pos. 1 (kinetic control) or in pos. 2 (thermodynamic control), which is in ortho or para to the activating substituent. So I would expect these products, in theory:
Image

I assume the contributing structures that represent the electron-donating effect are the following:
Image

Therefore, although I would expect a 6-acetyl derivative as a byproduct (at least in theory, since (4) might allow it), I don't understand why it is the main product. No clues at all about the 5-acetyl byproduct, since the 5-acetyl intermediate is not stabilized by the electron-donating effect: could it possibly be an error?

The second reaction is a bromination on 2-naphthol:
Image

Likewise, I can think that bromine would first go in pos. 1, and then, since it is only slightly deactivating, another bromine can be added. But again, why in pos. 6? Why not in pos. 3, in ortho to the activating substituent?

And in the end, are these reactions done under kinetic or thermodynamic control?
I am not an organic chemist! But if I remember my university organic chemistry the MeO group 'pushes' its electrons into the electron clouds above and below the aromatic rings. Thus, the para position becomes preferred in its reactivity. But I would also expect ortho and meta substitutes (impurities) in the solution.
I went to university 40 years ago so I think theory has improved in organic chemistry since then.
I wonder why you copied an organic chemistry question posted elsewhere 2 years ago and posted it in a chromatography forum :?:
Rndirk wrote:
I wonder why you copied an organic chemistry question posted elsewhere 2 years ago and posted it in a chromatography forum :?:



And they joined the Forum just to post this question.
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